degree in the temperature. But this rule is subject to so many variations as to be of no avail in practice. Among the cases of unusual variation and discrepancy between the pulse and the thermometer, the following have been gleaned from the records of European observers:

If any should have failed to consider the subject of thermometry in diagnosis, it may not at once seem clear to them that the noting of so slight a variation can be of any practical application. But careful consideration will convince them, we think, that, in very many cases requiring acute discrimination, we may, by the aid of the thermometer, so exclude the similar diseases as to render our diagnosis almost certain.

We would here hastily refer to a few of those diseases which, by the unwary practitioner, might be mistaken the one for the other; and we think a mere reference to them will show that, if we were able to exclude inflammatory action, either general or local, a diagnosis would be comparatively easy. This the thermometer generally enables us to do.

Pleurodynia may at times be mistaken for pleurisy. But, if

the temperature of the body be not above 98.5°, the maximum of health, we may be certain the disease we have encountered is not pleurisy.

Peritonitis, and a hyperæsthesia of the abdominal walls, are in a like manner distinguished by an abnormal or a normal temperature, respectively.

Pneumonia may be simulated by hysteria, and in the early stage of the disease, when the physical signs would naturally be absent or not marked, the diagnosis may be far from easy; but the thermometer is the unerring guide in such a case, which even the will of woman cannot falsify.

Prof. Austin Flint, in the New York Medical Journal for November, 1866, narrates the following case:

"A young German emigrant was admitted into hospital with vomiting and diarrhoea, and no previous history was obtained. The dejections were not choleraic, and both diarrhoea and vomiting were promptly arrested. The urine was scanty, and not albuminous; the pulse was frequent and feeble; the surface presented marked capillary congestion, and he was greatly prostrated. On the third day he was somnolent, and he gradually became comatose without the occurrence of convulsions.

"After the coma was developed, he came under my observation; and the diagnostic problem was, whether the coma depended on uræmia, on cerebral meningitis, or on typhus fever. Narcotism was excluded, inasmuch as the respirations were not diminished in frequency, and the pupils were not contracted. The symptoms pointed strongly to uræmia; but it was desirable to exclude effectually typhus fever and meningitis. This was done by the thermometer, which showed the heat of the body to be 97.5o.

"The patient succumbed, and autopsical appearance, in connection with the history during life, led to the conclusion that the patient, when admitted into the hospital, was in the stage of reaction after an attack of epidemic cholera."

§ III.-13

Dr. Compton, in Part 54 of Braithwaite's Retrospect, reports the following:

He gave an

This at first

"W. H., aged 29, a well-nourished man, of rather sallow complexion, and somewhat excited manner, having an occasional spasmodic way of speaking, complained, on admission, of sore throat; and, on examination, both tonsils and the back of the pharynx were seen to be considerably inflamed. imperfect history of having been ill about a week. sight seemed to be merely a somewhat severe case of tonsilitis, and no further examination seemed necessary; and the case was left to be made out by the clinical clerk before the visit next day. Finding, however, the man's temperature to be 105.4°, I was interested in the case, and I made out, on examination, the existence of partial trismus, and that the tongue, when protruded, deviated slightly towards the right side. The prognosis was deemed unfavorable. The man died within twelve hours of admission, the case being one of septicemia."

Having thus given an imperfect idea of the importance of thermometric observations in diagnosis, we will proceed to speak of the special diseases in which its use is most frequently demanded.

In the treatment of typhoid fever and typhus, the thermometer will be found especially useful to the general practitioner. By its aid diagnosis may be assured before the eruption makes its appearance, and by its careful observation prognosis is assisted, and rendered much more certain. Wunderlich notes the following as the normal course of Typhoid Fever:

The points most worthy of notice in the above record are,

1. The gradual increase of temperature during the first week, until the maximum is reached on the evening and morning of the sixth day.

2. That this maximum is rarely greater than 104°.

3. The noticeable difference of nearly 2° between the morning and evening range.

In strong contrast with this disease, typhus, after reaching a high degree, generally 104°, has a sudden rise of temperature, frequently to 107°. In typhus we also find the pulse and temperature rising simultaneously, and so rapidly that, even on the second day, the thermometer frequently stands as high as 103°; while the average of the seventh day is, pulse 110-140, temperature 104°.

A case in my own practice, of typhoid fever strongly simulating typhus, may assist in presenting the characteristics of the two diseases more clearly. It is that of Miss F. McG., aged 15. The record was as follows:

In typhus the heat of the body, moreover, is continuous throughout the day, there being rarely a degree of difference between that in the morning and evening, even to the middle of the second week. The defervescence is not gradual as in typhoid, but frequently the temperature will return to the normal standard in the course of thirty-six hours.

Briefly, then, it may be stated, that, with typhoid symptoms, but a temperature of less than 103.5 on the evening of the fourth or fifth day, the disease is not typhoid fever. If, between the eighth and tenth day, the evening temperature is less than 103°, the disease is not typhoid. If, on the first or second day, the thermometer exhibits a temperature of 104° or above, the disease is not typhoid fever. Thus we have striking symptoms